A case of pheochromocytoma with transient hyperinsulinemia and reactive hypoglycemia.

Hyperglycemia is a common symptom of pheochromocytoma. In the present paper, a 57-year-old man with transient hyperinsulinemia and reactive hypoglycemia is reported. His blood pressure was 100/50 mmHg. Following 75 g oral glucose intake, his blood sugar and insulin levels were 150 mg/dl and 15 mu Iu/ml at 0 min, 373 mg/dl and 757 mu Iu/ml at 60 min and 34 mg/dl and greater than 1,000 mu Iu/ml at 120 min, respectively. High plasma epinephrine and norepinephrine levels and histological findings of adrenal tumor confirmed the diagnosis of pheochromocytoma. Pheochromocytoma should be considered as one of the diseases which account for unexplained transient hyperinsulinemia with reactive hypoglycemia.